Digital videos are generally accessed in a sequential or linear fashion (e.g., one frame after another). As a result, browsing digital videos can be more inefficient than browsing some other types of digital content (e.g., text documents). Many techniques have been developed to provide an improved browsing experience for digital videos.
For example, video analysis algorithms have been developed for detecting certain features within frames of a digital video. The typical features detectable include speech detection, image/face detection, motion detection, laughter detection, etc. The detected feature(s) can be used to extract certain relatively more interesting frames. The extracted frames are usually presented in chronological order to a user and may be combined with other information (e.g., audio, closed-caption, etc.) into a more meaningful summary of the digital video (e.g., a still or motion storyboard).
A score (or other value) may be explicitly or implicitly assigned to one or more frames of a digital video when certain features are detected (or are absent). For example, whenever motion is detected in a frame, that frame may be assigned a score of “1.” Conversely, if no motion is detected in a frame, that frame may be assigned a score of “0.” Such assigned scores may be used to enable variable speed playback of the digital video. For example, frames having less motion (as indicated by a lower score) may be played at a faster rate and frames having more motion (as indicated by a higher score) may be played at a slower rate. Thus, it is possible for a video system to be configured to automatically adjust its playback speed, as a function of time, such that the user is given more time to view frames depicting greater levels of activity, while spending less time on frames depicting lower levels of activity.
However, existing techniques do not allow a user to dynamically change the scores assigned to the frames of the digital video to dynamically change the playback speed. The user can only view the video at the variable playback speed determined by the system.
Thus, a market exists for an improved digital video playback technique in which the playback speed may be varied by dynamically adjusting scores assigned to portions of the digital video.